Preheat oven to 180°C. Grease two 20cm (base measurement) round cake pans. Line bases with baking paper and dust sides with flour, shaking off excess.
Place a sheet of baking paper on a clean work surface. Sift over combined flour and cornflour. Repeat 2 more times.
Use an electric mixer to whisk eggs and sugar in a large bowl for 8-10 mins or until the mixture is light and fluffy and doubled in size. Gently sift the flour over the egg mixture. Use a metal spoon or balloon whisk to carefully and gently fold the flour through the egg mixture until almost combined. Combine butter and 2 tbs boiling water in a small jug. Pour down the side of the bowl. Carefully fold until just combined.
Divide between prepared pans. Bake for 20 mins or until cakes are dry and have shrunk away from the sides.
Turn the cakes onto wire racks lined with baking paper. Carefully peel the paper away from the base of each cake. Set aside to cool completely.
Use an electric mixer to whisk the cream and icing sugar in a bowl until soft peaks form.
Place 1 cake on a serving plate. Spread with jam and top with whipped cream mixture. Top with remaining cake.
To make the icing, sift the icing sugar into a medium bowl. Gradually add the passionfruit pulp, stirring until a smooth, glossy paste forms. Spread over the top of the cake. Set aside for 15 mins to set.